Please Explain The Quote: “adopting The Right Attitude Can Convert A Negative Stress Into A Positive One”?

It means that you can turn stressful situations into positive opportunities by having the right attitude about them. You can look at a potential obstacle or stressor in your life and do one of two things. You can either have a bad attitude about it, be pessimistic, assume the worst, and let it ruin your life, or you can be positive about it, see it as a potential opportunity to show your strength, and use it to your advantage.
Two people with two different attitudes will look at the same problem in their life and go completely different ways with it. Let’s say you don’t get into the 4-year university you wanted to get into. A person with a bad attitude would say things like, “I must be so stupid since I didn’t get in, I’m never going to get a degree, I’m a moron, the school hates me, I did something wrong, etc.” and they may not even try applying again because they think they are so stupid. A person with a better attitude might turn it around and say, “Well, it’s a really prestigious school, so a lot of really smart people applied. That doesn’t make me stupid, it just means I didn’t make the very top cut. I will go to community college for two years first, get my grades up, and then show them how smart I am so that when I re-apply in two years, they will definitely accept me.”
Hope that helps.

having the right attitude is everything. if you have the right attitude there won’t be any negative stress at all. everything in life starts with you so you need to do only that what pleases you and not what others think about you or care about you.